1. Technical Field
The present invention relates to a method of producing a transfer medium, a set of ink and adhesive liquid used for the method, a transfer medium, and an apparatus for producing the transfer medium.
2. Related Art
There is known a transfer medium transferring letters or image patterns formed by attaching ink onto a substrate to a target. Regarding the transfer medium, there is known a technique in which adhesive liquid is coated on a pattern according to the shape of the pattern by using, for example, a screen printing plate, as described in JP-A-7-314879.
However, when letters, image patterns, or adhesive liquid patterns are formed using a printing plate of screen printing, flexo printing, gravure printing, or the like, production costs increase in small quantity batch production. Therefore, in order to suppress the production costs to be low in small quantity batch production, a method in which the letters or patterns are formed by discharge of ink from an ink jet head has been suggested.
However, when the letters, the image patterns, and the adhesive liquid patterns are formed using a printing plate of flexo printing, gravure printing, or the like as well as the screen printing plate, production costs increase for small quantity batch production of the transfer medium. Therefore, in order to suppress the production costs to be low in small quantity batch production of the transfer medium, a method of producing a transfer medium is considered in which ink and adhesive liquid are discharged from an ink jet head so as to be attached to a substrate, whereby a colored layer created by the ink and an adhesive layer created by the adhesive liquid are formed on the substrate in sequence.
Herein, the following properties are required for the ink discharged from the ink jet head to form the colored layer and for the adhesive liquid discharged from the ink jet head for forming the adhesive layer.
First, it is required for the ink and the adhesive liquid to have excellent discharge stability when the ink jet head is driven at a high frequency.
Second, in a process of forming the pattern of the adhesive layer by attaching the adhesive liquid on the pattern of the colored layer, it is required that letters or images of a high resolution are obtained without a case where the colored layer pattern runs or becomes messed up.
Third, it is required that a thermoplastic resin configuring the adhesive layer is efficiently distributed on the colored layer pattern, and that the resultant exhibits an excellent transfer property when being used as the transfer medium, without causing defective transfer of fine letters and transfer unevenness of images.
Fourth, it is required that excellent adhesiveness is exhibited after transfer between a medium to be transferred or the colored layer and the adhesive layer.